Without large population studies, the promise of the Human Genome project and personalized genomic medicine will remain unfulfilled in significant ways. Sufficiently large numbers of individuals from a wide variety of backgrounds enrolled in cohort studies are going to be the keystone of many of the genomic translational discoveries. Concerns about privacy, data security and disclosure are among the predictable obstacles to the generation of large and sustainable genomically and clinically annotated cohorts. Giving patients control of the use of their health data will provide a practical mechanism for harnessing the volunteerism of our populations and gathering research data. We are proposing an extension of a longstanding, leading, National Library of Medicine-funded project in Personally Controlled Health Records systems (PCHR's), the PING (Personal Internetworked Notary and Guardian) project to address the challenges of curating and communicating personal genomic data. We call this the Genomic PING (GPING) project. G-PING entails the following specific aims: 1: Construct Genomic PING (G-PING) for managing raw and processed genomic data. 2: Develop quanitative risk models for patients and their relatives. 3: Design and evaluate a user interface to communicate disclosure. In concert with appropriate non-discrimination legislation, G-PING lays the groundwork for large-scale genomic cohort studies.